La Silla Observatory

ESO's first observatory

The La Silla Observatory is located on the outskirts of the Chilean Atacama Desert, 600 km north of Santiago de Chile and at an altitude of 2400 metres. Like other observatories in this geographical area, La Silla is located far from sources of light pollution and, like the Paranal Observatory, home to the Very Large Telescope, it has one of the darkest night skies on the Earth. La Silla has been an ESO stronghold since the 1960s. Here, ESO operates two of the most productive 4-metre class telescopes in the world.

The 3.58-metre New Technology Telescope (NTT) broke new ground for telescope engineering and design and was the first in the world to have a computer-controlled main mirror (active optics), technology developed at ESO and now applied to most of the world's current large telescopes.

A tour of the La Silla Observatory

Chile night time only! During the day the webcam shows the last frame before sunrise. The red letters indicate telescopes that are observing right now (T—the ESO 3.6-metre telescope, N— New Technology Telescope and D—the MPG/ESO 2.2-metre telescope). Please, see more on La Silla - All Sky Camera.

Visit the La Silla Observatory

Science with the Telescopes at La Silla

With about 300 refereed publications attributable to the work of the observatory per year, La Silla remains at the forefront of astronomy. La Silla has led to an enormous number of scientific discoveries, including several "firsts". The HARPS spectrograph is the undisputed champion at finding low-mass extrasolar planets. It detected the system around Gliese 581, which contains what may be the first known rocky planet in a habitable zone, outside the Solar System (eso0722). Several telescopes at La Silla played a crucial role in linking gamma-ray bursts — the most energetic explosions in the Universe since the Big Bang — with the explosions of massive stars. Since 1987, the ESO La Silla Observatory has also played an important role in the study and follow-up of the nearest recent supernova, SN 1987A.

Did you know?Stars form in dense clouds of the interstellar medium, but even in these densest regions the pressure is comparable to the most tenuous vacuum created in a laboratory on Earth. In these clouds, the temperatures are below -200 degrees Celsius.

Did you know?Stars form in dense clouds of the interstellar medium, but even in these densest regions the pressure is comparable to the most tenuous vacuum created in a laboratory on Earth. In these clouds, the temperatures are below -200 degrees Celsius.

Did you know?The skies over the ESO sites in Chile are so dark that on a clear moonless night it is possible to see your shadow cast by the light of the Milky Way alone.